Theme: Governance & development
Thursday, July 2
What strategy should be adopted to prioritise and develop de-impermeabilisation, greening and rainwater infiltration across the Grand Poitiers Urban Community ?
Despite elected officials' ambitions to develop Nature-Based Solutions, it is difficult to secure funding for these initiatives and to make them a priority or more legitimate than other public policies. It is now well established that urban greening is only relevant when part of a three-pronged approach involving ‘de-impermeabilisation, greening and rainwater infiltration’. To promote this strategy among elected officials, it is necessary to highlight, through various prioritisation studies (Canopy Plan, heat island studies, regulatory requirements for greening car parks, rainwater zoning, inter-municipal local urban development plan, sanitation master plan) all the other benefits of implementing this strategy, particularly in terms of health, well-being and combating urban heat islands. Based on these studies, the aim is to exploit all opportunities for work in which the implementation of this strategy can bring one or more additional benefits to those for which the investment was initially made.
How can engineering and environmental economics collaborate to manage urban stormwater in the face of global change?
We have long recognised that our climate, cities, communities and infrastructure are changing, and will continue to change, leading to increased risks associated with stormwater management. A vast number of technical solutions have been proposed, many of which have proven highly effective in specific case studies. However, despite the need and the technical interventions, stormwater challenges persist and, in many cases, have exacerbated over recent years. Funded by the NERC interdisciplinary fund, this project explores how closer collaboration between engineering and economics can enable translational science and inform stormwater management practice. The exploration took place through workshopping around 40 attendees from scientific, engineering, economic and policy backgrounds to identify the challenges and opportunities for stormwater management in the face of global change. From this evaluation, ten cross-cutting questions have been identified which have the potential for immediate investigation and actionable results. The interdisciplinarity of Novatech provides the ideal place to further explore and share these ideas to our international community.
Feedback on the interdepartmental consultation process during the modification of the rainwater management zoning of the City of Paris
As part of its climate change adaptation policy, the City of Paris has implemented in 2018 its first rainwater management zoning. A revision of this regulatory document has been initiated in 2023, with the aim of strengthening rainwater valorization in construction and public spaces projects. In order to involve several technical services of the City of Paris in this process of revision, a diagnosis and an inter-services consultation have been conducted. The objectives of this approach were to take account of the constraints and the practices of those services, to facilitate their appropriation of the new rules, and to stimulate multidisciplinary work on rainwater management. Thanks to an appropriate framing, the consultation has contributed to the successful completion of the revision. Furthermore, it has helped to broaden the discussion to other technical and organizational issues. Therefore, this inter-services work should continue to facilitate the implementation of the new zoning and the change of practices, towards a more integrated and virtuous rainwater management.
Designing, managing, and governing: Multifunctionality at the core of urban green infrastructure implementation - Focus on integrated stormwater management
The integration of multifunctionality—that is, the ability of an urban development to combine several functions, particularly ecosystem services—has become a major challenge for local authorities in the implementation and maintenance of Nature-based Solutions in urban areas. The study presented here was conducted from April to July 2025 using a sociotechnical approach. It focused on four case studies (the cities of Paris, Les Mureaux, Meudon, and Montigny-le-Bretonneux) and was based on interviews with 17 participants, including technical service staff, funders, contractors, experts, and one municipal elected official. The findings show that although multifunctional ambitions are widely asserted in political and technical discourse, their practical implementation faces constant trade-offs. Certain functions are prioritized: the hydrological function tends to be overshadowed by functions that are more immediately visible or valued, while spaces heavily used by the public can limit ecological potential, particularly biodiversity. Multifunctionality therefore does not appear as the simple, cumulative coexistence of multiple benefits, but rather as the outcome of compromises that reveal the paradox between stated ambitions and actual outcomes. Moreover, making multifunctionality operational requires overcoming institutional and technical silos and moving toward more cross-cutting, adaptive forms of governance capable of integrating the diversity of expected functions over time.